Present Value, Future Value, Rate

Hello. I am having a hard time determining which function I should be using to solve these problems. Can someone please put me on the right track????? Thanks to anyone that can help me.

Problem 1: Joe won a lottery jackpot that will pay him $12,000 each year for the next ten years. The market rate is currently 12%. How much does the lottery have to invest today to pay out this prize to Joe over the next ten years?

Problem 2: Mary just deposited $33,000 in an account paying 10% interest. She plans to leave the money in this account for seven years. How much will she have in her account at the end of the seventh year?

Problem 3: Mary and Joe would like to save up $10,000 by the end of three years from now. They currently have $2500 in a savings account. They would like to make equal year end deposits to this savings account to pay for furniture when they purchase it three years from now. This account pays 8% interest. How much should the year end payments be?

PLzzzzzzzz i neeed helpppppp

Hi ,plz i need ur help .i have an exam after couple of hours.

if a person was indebeted for $200 that was due after six months & $300 due after one year. if the lender approved of an 18% interst rate per year.Calculate the amount the borrower should ppay now.

if the borrower decided to pay both of the amounts after one year from now. calculate the amount he should pat in that date

plz help me soroban...